/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    bool hasPathSum(TreeNode *root, int sum) {
        if (root==NULL) return false;
        return (root->left==NULL && root->right==NULL && sum==(root->val))
            || hasPathSum(root->left, sum-root->val)
            || hasPathSum(root->right, sum-root->val);
    }
};
